Multiprocessing not working with progress bar in tkinter - python-3.x

Question

I'm attempting to get the progress bar to run while a method is running. The problem is when I set the method "generatePi" into the class it won't run simultaneously; however, when I set the method "generatePi" outside of the class it works.
The code with method in class that I can get to work is:
from tkinter import (Tk, BOTH, Text, E, W, S, N, END,
NORMAL, DISABLED, StringVar)
from tkinter.ttk import Frame, Label, Button, Progressbar, Entry
from tkinter import scrolledtext
from multiprocessing import Process, Manager, Queue
from queue import Empty
from decimal import Decimal, getcontext
DELAY1 = 80
DELAY2 = 20
q = Queue()
class Example(Frame):
def __init__(self, parent):
Frame.__init__(self, parent, name="frame")
self.parent = parent
self.initUI()
def initUI(self):
self.parent.title("Pi computation")
self.pack(fill=BOTH, expand=True)
self.grid_columnconfigure(4, weight=1)
self.grid_rowconfigure(3, weight=1)
lbl1 = Label(self, text="Digits:")
lbl1.grid(row=0, column=0, sticky=E, padx=10, pady=10)
self.ent1 = Entry(self, width=10)
self.ent1.insert(END, "4000")
self.ent1.grid(row=0, column=1, sticky=W)
lbl2 = Label(self, text="Accuracy:")
lbl2.grid(row=0, column=2, sticky=E, padx=10, pady=10)
self.ent2 = Entry(self, width=10)
self.ent2.insert(END, "100")
self.ent2.grid(row=0, column=3, sticky=W)
self.startBtn = Button(self, text="Start",
command=self.onStart)
self.startBtn.grid(row=1, column=0, padx=10, pady=5, sticky=W)
self.pbar = Progressbar(self, mode='indeterminate')
self.pbar.grid(row=1, column=1, columnspan=3, sticky=W+E)
self.txt = scrolledtext.ScrolledText(self)
self.txt.grid(row=2, column=0, rowspan=4, padx=10, pady=5,
columnspan=5, sticky=E+W+S+N)
def onStart(self):
self.startBtn.config(state=DISABLED)
self.txt.delete("1.0", END)
digits = int(self.ent1.get())
accuracy = int(self.ent2.get())
self.p1 = Process(target=generatePi(q, digits, accuracy), args=())
self.p1.start()
self.pbar.start(DELAY2)
self.after(DELAY1, self.onGetValue)
def onGetValue(self):
if (self.p1.is_alive()):
self.after(DELAY1, self.onGetValue)
return
else:
try:
self.txt.insert('end', q.get(0))
self.txt.insert('end', "\n")
self.pbar.stop()
self.startBtn.config(state=NORMAL)
except Empty:
print("queue is empty")
def generatePi(q, digs, acc):
getcontext().prec = digs
pi = Decimal(0)
k = 0
n = acc
while k < n:
pi += (Decimal(1)/(16**k))*((Decimal(4)/(8*k+1)) - \
(Decimal(2)/(8*k+4)) - (Decimal(1)/(8*k+5))- \
(Decimal(1)/(8*k+6)))
k += 1
q.put(pi)
def main():
root = Tk()
root.geometry("400x350+300+300")
app = Example(root)
root.mainloop()
if __name__ == '__main__':
main()
The code with method outside class that I am unable to get to work:
from tkinter import (Tk, BOTH, Text, E, W, S, N, END,
NORMAL, DISABLED, StringVar)
from tkinter.ttk import Frame, Label, Button, Progressbar, Entry
from tkinter import scrolledtext
from multiprocessing import Process, Manager, Queue
from queue import Empty
from decimal import Decimal, getcontext
DELAY1 = 80
DELAY2 = 20
q = Queue()
class Example(Frame):
def __init__(self, parent):
Frame.__init__(self, parent, name="frame")
self.parent = parent
self.initUI()
def initUI(self):
self.parent.title("Pi computation")
self.pack(fill=BOTH, expand=True)
self.grid_columnconfigure(4, weight=1)
self.grid_rowconfigure(3, weight=1)
lbl1 = Label(self, text="Digits:")
lbl1.grid(row=0, column=0, sticky=E, padx=10, pady=10)
self.ent1 = Entry(self, width=10)
self.ent1.insert(END, "4000")
self.ent1.grid(row=0, column=1, sticky=W)
lbl2 = Label(self, text="Accuracy:")
lbl2.grid(row=0, column=2, sticky=E, padx=10, pady=10)
self.ent2 = Entry(self, width=10)
self.ent2.insert(END, "100")
self.ent2.grid(row=0, column=3, sticky=W)
self.startBtn = Button(self, text="Start",
command=self.onStart)
self.startBtn.grid(row=1, column=0, padx=10, pady=5, sticky=W)
self.pbar = Progressbar(self, mode='indeterminate')
self.pbar.grid(row=1, column=1, columnspan=3, sticky=W+E)
self.txt = scrolledtext.ScrolledText(self)
self.txt.grid(row=2, column=0, rowspan=4, padx=10, pady=5,
columnspan=5, sticky=E+W+S+N)
def onStart(self):
self.startBtn.config(state=DISABLED)
self.txt.delete("1.0", END)
digits = int(self.ent1.get())
accuracy = int(self.ent2.get())
self.p1 = Process(target=self.generatePi(q, digits, accuracy), args=())
self.p1.start()
self.pbar.start(DELAY2)
self.after(DELAY1, self.onGetValue)
def onGetValue(self):
if (self.p1.is_alive()):
self.after(DELAY1, self.onGetValue)
return
else:
try:
self.txt.insert('end', q.get(0))
self.txt.insert('end', "\n")
self.pbar.stop()
self.startBtn.config(state=NORMAL)
except Empty:
print("queue is empty")
def generatePi(self, q, digs, acc):
getcontext().prec = digs
pi = Decimal(0)
k = 0
n = acc
while k < n:
pi += (Decimal(1)/(16**k))*((Decimal(4)/(8*k+1)) - \
(Decimal(2)/(8*k+4)) - (Decimal(1)/(8*k+5))- \
(Decimal(1)/(8*k+6)))
k += 1
q.put(pi)
def main():
root = Tk()
root.geometry("400x350+300+300")
app = Example(root)
root.mainloop()
if __name__ == '__main__':
main()
With the change in code being:
self.p1 = Process(target=generatePi(q, digits, accuracy), args=())
To:
self.p1 = Process(target=self.generatePi(q, digits, accuracy), args=())

Answer 1

I got same problem when I try it I find windows system seems react late but in terminal it's actually running